The present invention relates to helically reinforced tubing or hose, and to an apparatus for and method of production of tubing or hose having characteristics that may progressively vary along continuous selected lengths of the tubing or hose, thereby enabling the resulting tubing or hose to incorporate lengths that increase or diminish in diametrical size, wall thickness and pitch, as may be desired for use in specific applications.
Tapered tubing or hose has many proposed commercial, industrial and medical uses. Commercially, a tapered length of tubing or hose can be used to improve air flow and reduce the accumulation of debris within the tubing or hose. An aspect of the invention permits tapered tubing or hose to be provided with a helical reinforcing rib that may be formed into a substantially constant diameter rigid or semi-rigid cuff near where severed to provide end regions that may connect with existing fittings or devices, or for use as a wand to vacuum yard debris from around obstacles, or as a wand to direct high velocity air generated by leaf blowers or blowing equipment that delivers seed, mulch, insulation or the like. Another aspect of the invention permits a tapered region of tubing or hose to be designed with a correct taper length, curve or angle to provide a desired air or gas velocity for substantially any given application.
Industrially, tapered tubing or hose can be used to eliminate the need for multiple connectors and adapters in fume exhaust systems as the inside diameter can be varied to create a proper air flow and velocity for any given application—which will also diminish the overall weight and cost of the system. Likewise, substantially the same design principal can be used to provide tapered tubing or hose to transport such items as grain or other granular materials including plastic pellets and other “flowable” raw materials.
Medically, a tapered, lightweight, highly flexible tubing or hose (which can be relatively easily and continuously produced by the techniques of the present invention) is useful for exhausting gases from areas where surgery is being performed, and is especially useful in providing breathing conduits used with sleep apnea equipment and other medical devices related to breathing.
One particularly desirable use of tapered tubing or hose manufactured in accordance with features of the present invention has to do with the treatment of sleep apnea. Thousands of people suffer from sleep apnea, which causes those who have the affliction to repeatedly stop breathing while they sleep, sometimes hundreds of times a night. Breathing pauses can occur more than 30 times per hour, and may each last several seconds or may continue for a minute or more. The result is that those who have sleep apnea are more likely to be involved in accidents, and they are at risk for such complications as diabetes, heart disease and stroke.
Sleep apnea results from a closure of the airway of the person who has the affliction. A common treatment for sleep apnea centers about keeping a patient's airway open during sleep through use of a “Continuous Positive Airway Pressure” unit that blows air into a person's nose—sometimes the mouth, too—forcefully enough to keep the back of the throat open. In simple terms, a so-called “CPAP machine” includes a pump, a length of tubing or hose, and a face mask.
The tubing or hose of a CPAP machine consists of either a single large diameter length of tubing or hose running from the pump to the mask, or a relatively large diameter length of tubing or hose running from the pump to a combination swivel coupling and reducer fitting located about 18 to 24 inches away from the mask, where tubing or hose diameter is reduced or diminished to provide a more flexible length of tubing or hose leading to the mask that still is able to provide adequate air flow and pressure.
While CPAP machines have gotten smaller, quieter and more sophisticated over the years, about half of the patients who need them can't or won't use them, for a variety of reasons. For example, the mask can be claustrophobic, get in the way of glasses, or may fall off during the night. The tubing or hose that delivers air to the mask may prevent someone from sleeping on his or her stomach, or from rolling over. Indeed, many of those who have tried to use CPAP machines have complaints about the awkward nature of the air supply tubing or hose, which often result in these machines being used mainly as doorstops.
By replacing the clumsy combination of a larger then smaller diameter tubing or hose (typically joined by a combination of swivel connectors and reducer fittings) with quite a simple and lightweight, one-piece reach of tapered tubing or hose, CPAP units can be provided with a much improved, easy-to-flex breathing circuit, thereby rendering these machines far more acceptable for use by patients who need them. In accordance with features of the present invention, a tapered length or tubing or hose can be provided for CPAP machines, with the tubing or hose having such characteristics as variable pitch, wall thickness and helix size that is designed to achieve a much more desirable feel and provide an easier flow of air than provided by the presently used arrangement of a dual diameter set of tubes or hoses joined by a combination reducer and swivel coupling. Indeed, in accordance with features of the present invention, a tapered length of tubing or hose for use with a CPAP machine can be manufactured in such a way as to reduce or to even eliminate a pressure drop along the length of a tubing or hose circuit, or to increase or decrease air velocity or pressure in the tubing or hose circuit, as desired.
It is also possible, using features of the present invention, to provide CPAP machines with a one-piece, helically reinforced tapered length of tubing or hose of any desired diameter or having a desired change in diameter provided anywhere that is desired along the length of the tubing or hose, perhaps including an enlarged “belly” (i.e., an area of significantly enlarged diameter) for use as a decompression chamber, water trap or accumulator, which some patients require. Likewise, variable diameter flexible tubing or hose products produced using techniques of the present invention give a designer of tubing or hose system circuitry many options not currently available without the use of clumsy couplings and fittings that add cost and weight to a tubing or hose system while reducing flexibility and other desired performance characteristics.